This invention pertains to video programs containing interactive links.
It is known in the art to provide video. information containing interactive links; The video information can be in the form of a video movie, television program, or other type of video clip. Embedded within the video is one or more. interactive links. This means that during the video, a user can move a cursor over an object of interest and click on that object, e.g. using a mouse, touch pad, track ball, or other type of device. This activates a link, e.g. to a web page, a piece of software, or other source of information. The way this might work is as follows. Suppose a viewer is watching a video clip of an auto race on a television screen 1, and there are several automobiles 2, 3 visible on screen 1. Suppose the viewer desires further information concerning the driver of one of the automobiles (e.g. automobile 2). He might click on automobile 2 and activate a web page. link that will cause his television to display a web page providing information concerning the car and driver.
In order for such a system to function, the viewer""s television system must receive a video signal corresponding to the program he is watching. The viewer""s television system must also receive data identifying the source of information if the viewer clicks on a particular object displayed on the screen. For example, if the link is to a web site page, the viewer""s television system must receive the URL (or other addressing means) for identifying which web page should be displayed if the viewer clicks on that object.
The viewer""s television system must also receive data corresponding to the location of the xe2x80x9cactive areaxe2x80x9d on the television screen. The active area is that portion of the area of the television screen that the viewer will click on in order to access the desired link. Thus, in the case of the automobile race, the active area corresponding to a particular automobile in the race should be a portion of the screen area where the automobile is shown, e.g. as identified by dotted lines 6. (The position the active area may or may not be visually indicated on television screen 1.)
There are several ways for the television system to determine where active area 6 should be. One way is to design the television system such that it has pattern recognition capabilities, and can recognize where automobile 2 is located. Unfortunately, this would make television 1 quite expensive. Alternatively, for each frame of the video, one could communicate to the television system where active area 6 is to be located. Unfortunately, this would require a considerable amount of bandwidth, since the size and location for each active area on the screen would have to be communicated to the television system. This would have to be done for each frame of the video. (During the automobile race, automobiles 2 and 3 move about screen 1. Thus, the location and size of the active areas associated with automobiles 2 and 3 must be constantly updated.) Also, there could be many active areas on the screen, each corresponding to a link to a web page. Accordingly, it would be desirable to communicate information concerning the location and/or size of the active area for each frame without having to use a large signal bandwidth.
A video signal is provided to a video system. In accordance with our invention, the location of one or more active areas associated with the video signal is communicated to the video system for some of the frames of the video signal, but not other frames of the video signal. The video system determines the location of the one or more active areas for the other frames by interpolation. In this way, instead of having to provide data to the video system concerning the active area locations for each frame, such data is provided only for selected frames, and the video system calculates where the active areas for the other frames should be by interpolating, e.g. using either a linear interpolation technique or a spline interpolation technique. Because the source of the video signal need not provide active area information for each frame of the signal, the bandwidth requirements for communicating this information are reduced.
In one embodiment, not only is the location of the active area communicated in this way, but the size of the active area is communicated in this way as well.
In accordance with another aspect of the invention, a video signal comprising a set of frames is communicated along with the location of an active area for some of the frames but not others of the frames. The active area corresponds to an object depicted in those frames. The object can be a product, a person, a cartoon character or anything else that can be depicted in a video. As mentioned above, the active area is not communicated for the others of the frames, although the object is depicted in the others of the frames. A receiving system calculates the location of the active area by interpolation based on the location of the location of the active area for said some of the frames. In this way, bandwidth requirements for communicating the location of the active areas is reduced.